In the last few years gluten-free products have become increasingly popular, but a gluten-free diet was originally created as a medical treatment for those suffering from celiac disease. Research shows nearly 80 percent of Americans on a gluten-free diet do so without a proper diagnosis of celiac disease.

Nearly 1.8 million Americans have celiac disease, but approximately 1.4 million of them are unaware of it, while there are 1.6 million individuals who practice a gluten-free diet, despite not being diagnosed by their doctor.

Celiac disease is a digestive disorder that damages the lining of the small intestine, which prevents it from absorbing parts of food that are essential for a healthy diet. This condition is triggered when affected individuals consume the protein gluten. Currently the only medical treatment prescribed is a gluten-free diet.

According to co-author Joseph Murray, M.D., a Mayo Clinic gastroenterologist, there are millions people on a gluten-free diet, and it's unclear what the medical need is, but if someone believes they may suffer from celiac disease, they should seek medical help before beginning a gluten-free diet.

Dr. Murray and his colleagues combined blood tests from confirmed celiac disease with interviews from the Centers for Disease Control and Prevention's nationwide population sample survey called National Health and Nutrition Examination Survey. This survey assisted researchers in that it was uniquely generated to give accessibility to physicians and researchers alike regarding the health and nutrition of U.S. adults and children. It combines both interviews and physical examinations.

Dr. Murray and colleagues uncovered that celiac disease is much more common in Caucasians.

"In fact, virtually all the individuals we found were non-Hispanic Caucasians," says co-author Alberto Rubio-Tapia, MD, a Mayo Clinic gastroenterologist.

Additionally, data demonstrates the rate of celiac disease in the U.S. is comparable to the rates found in several European countries.

Dr. Murray proposes physicians are not doing a great job at detecting celiac disease. "If you detect one person for every five or six (who have it), we aren't doing a very good job detecting celiac disease," he said.

The study was published in American Journal of Gastroenterology.